[TowerTalk] another stupid guywire question

[Jim Brown]

On Thu, 17 Jul 2008 09:28:18 -0700 (PDT), Rick Karlquist wrote:

>The is a fallacy here to the effect that non-resonant conductors
>will not distort the antenna pattern.  Although resonant conductors
>are worse than non-resonant, any grounded conductor over 1/6 wl
>and an floating conductor over 1/3 wl will affect the pattern.
>Some quick modeling with EZNEC will bring you the bad news.

Yes. Although the orientation and location of the conductor can 
strongly affect the level of interference. To see an example of 
this, see pages 60-65 of 

http://audiosystemsgroup.com/NCDXACoaxChokesPPT.pdf

especially the calculated results of the NEC model on p 62. Note 
that I added the chokes to fix a real problem -- the vertical had 
worked before I added the other antennas with their feedlines! So 
here's an example of "theory" and "practice" being beautifully in 
agreement. 

73,

Jim Brown K9YC